Recent content by digipony

  1. D

    Eigenvalues of Matrix Function

    Then for all eigenvalues... λ=tn f(T)v=f(tn)v , therefore f(B) has eigenvalues f(t1), f(t2),... f(tn)
  2. D

    Eigenvalues of Matrix Function

    Then f(T)v=(f0+f1T +f2T2...)v = (f0+f1t1 +f2t2...)v =f(t1)v
  3. D

    Eigenvalues of Matrix Function

    So you'd have T2v=t2v ... Tnv=tnv
  4. D

    Eigenvalues of Matrix Function

    Homework Statement Define a matrix function f(T) of an nxn matrix T by its Taylor series f(T)=f0 +f1T +f2T2+... Show that if matrix T has the eigenvalues t1,t2...tn, then f(T) has eigenvalues f(t1), f(t2)...f(tn) Homework Equations The Attempt at a Solution I am at a loss of how...
  5. D

    Is the Dot Product of Two Vector Pairs Always Commutative?

    Darn- it made the problem so easy, but I guess that was a sign that I was probably doing something that I should not be doing. Thank you for explaining why I could not shuffle the vectors around. :) I did try an example, however it worked out. But I guess it wasn't that good of an example since...
  6. D

    Is the Dot Product of Two Vector Pairs Always Commutative?

    Homework Statement The Attempt at a Solution I am working a physics problem and want to make sure I'm not making a mistake in the math. Here is my math inquiry: Say you have (a*b)(c*d) where * indicates the dot product, and a,b,c, and d are all vectors. Can you say that (a*b)(c*d) =...
  7. D

    Factoring Out Ckq in Summation: Proper or Breaking Rules?

    Ok, I will try to prove it without summation notation. Thank you
  8. D

    Factoring Out Ckq in Summation: Proper or Breaking Rules?

    Homework Statement Prove the relation det(AB)=det(A)det(B)Homework Equations det A = \sum_{k}A_{kq} C_{kq} The Attempt at a Solution Here is what I have done: (detA)(detB)= \sum_{k}A_{kq} C_{kq} \sum_{k}B_{kq} C_{kq} = \sum_{k}(A_{kq}B_{kq}) C_{kq} = \sum_{k}(AB)_{kq} C_{kq} =det(A+B) My...
  9. D

    Know of any Funny Physics Jokes for Shirts?

    Does anyone know of any good Physics jokes/comics that would be good for a physics group's tshirts and care to share? It's ok if they have a sexual innuendo, but these are for an University organization, so if it has a dirty overtone, it has to be subtle/decent. (To give you some sense of what...
  10. D

    Finding the Density of States of Radiation Oscillators

    Thank you! I looked for hours trying to find something that makes sense but nothing clicked until ^ this article.
  11. D

    Finding the Density of States of Radiation Oscillators

    Homework Statement Calculate the density of states if the radiation oscillators are confined to a square (i.e. in two dimensions).Homework Equations The Attempt at a Solution This was one of the questions for my Modern Physics class, (we recently covered blackbody radiation), although based on...
  12. D

    Impedance vs Resistance: Understanding the Distinction in Circuit Elements

    Just wondering here... What is the difference between impedance and resistance? Is resistance typically used to describe the nature of a circuit element, while impedance is of an entire circuit? I have looked up the definitions for both, and I just don't see the difference between them. Thanks!
  13. D

    General Lens Question: Diverging or Converging

    Never mind: figured it out. If the curvature of the first lens is greater, then it is converging. If the curvature of the second lens is greater, it is diverging.
  14. D

    General Lens Question: Diverging or Converging

    Homework Statement General question here: If I have a lens that looks like two concave lenses put together (I believe it is called a Meniscus), how do I conceptually tell whether the lens should be converging or diverging? I think I remember reading something saying that it depends upon which...
  15. D

    Laplace Transform of Delta Function

    Oops-Typing error. Thanks! :)
Back
Top